1,143 research outputs found

    Aphakia-Its Optics and Intraocular Lens

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    Curating Transient Population in Urban Dynamics System

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    For past several decades, research efforts in population modelling has proven its efficacy in understanding the basic information about residential and commercial areas, as well as for the purposes of planning, development and improvement of the community as an eco-system. More or less, such efforts assume static nature of population distribution, in turn limited by the current ability to capture the dynamics of population change at a finer resolution of space and time. Fast forward today, more and more people are becoming mobile, traveling across borders impacting the nuts and bolts of our urban fabric. Unfortunately, our current efforts are being surpassed by the need to capture such transient population. It is becoming imperative to identify and define them, as well as measure their dynamics and interconnectedness. In this work, we intend to research urban population mobility patterns, gauge their transient nature, and extend our knowledge of their visited locations. We plan to achieve this by designing and developing novel methods and using VGI data that models and characterizes transient population dynamics

    Retained Intra-orbital foreign bodies : A Short Case Series

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    ABSTRACT Intraorbital foreign in different forms are seen quite commonly in all age groups. These objects can be classified according to their compositionas (1) metallic, such as steel; (2) non-metallic, which may be inorganic, such as glass; and (3) organic, such as wood or vegetable matter. In general, injuries caused by metal and glass are well-tolerated and, if they do not have any symptoms or signs, may be left in situ, whereas organic matter, such as wood and vegetable matter, is poorly tolerated, triggers an intense inflammatory. They require prompt and adequate management for salvaging the patients vision. This retrospective case report reviews the clinical features, appearance and management of four cases with intraorbital foreign bodies where the normal vision of the patient was retained

    Retained Intra-orbital foreign bodies : A Short Case Series

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    ABSTRACT Intraorbital foreign in different forms are seen quite commonly in all age groups. These objects can be classified according to their compositionas (1) metallic, such as steel; (2) non-metallic, which may be inorganic, such as glass; and (3) organic, such as wood or vegetable matter. In general, injuries caused by metal and glass are well-tolerated and, if they do not have any symptoms or signs, may be left in situ, whereas organic matter, such as wood and vegetable matter, is poorly tolerated, triggers an intense inflammatory. They require prompt and adequate management for salvaging the patients vision. This retrospective case report reviews the clinical features, appearance and management of four cases with intraorbital foreign bodies where the normal vision of the patient was retained

    Prompt and non-prompt J/ψ production at midrapidity in Pb-Pb collisions at √sNN=5.02 TeV

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    The transverse momentum (pT) and centrality dependence of the nuclear modification factor RAA of prompt and non-prompt J/ψ, the latter originating from the weak decays of beauty hadrons, have been measured by the ALICE collaboration in Pb–Pb collisions at sNN = 5.02 TeV. The measurements are carried out through the e+e− decay channel at midrapidity (|y| < 0.9) in the transverse momentum region 1.5 < pT < 10 GeV/c. Both prompt and non-prompt J/ψ measurements indicate a significant suppression for pT > 5 GeV/c, which becomes stronger with increasing collision centrality. The results are consistent with similar LHC measurements in the overlapping pT intervals, and cover the kinematic region down to pT = 1.5 GeV/c at midrapidity, not accessible by other LHC experiments. The suppression of prompt J/ψ in central and semicentral collisions exhibits a decreasing trend towards lower transverse momentum, described within uncertainties by models implementing J/ψ production from recombination of c and c ̄ quarks produced independently in different partonic scatterings. At high transverse momentum, transport models including quarkonium dissociation are able to describe the suppression for prompt J/ψ. For non-prompt J/ψ, the suppression predicted by models including both collisional and radiative processes for the computation of the beauty-quark energy loss inside the quark-gluon plasma is consistent with measurements within uncertainties

    Photoproduction of K+ K- Pairs in Ultraperipheral Collisions

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    K+K- pairs may be produced in photonuclear collisions, either from the decays of photoproduced φ(1020) mesons or directly as nonresonant K+K- pairs. Measurements of K+K- photoproduction probe the couplings between the φ(1020) and charged kaons with photons and nuclear targets. The kaon-proton scattering occurs at energies far above those available elsewhere. We present the first measurement of coherent photoproduction of K+K- pairs on lead ions in ultraperipheral collisions using the ALICE detector, including the first investigation of direct K+K- production. There is significant K+K- production at low transverse momentum, consistent with coherent photoproduction on lead targets. In the mass range 1.1<1.4 GeV/c2 above the φ(1020) resonance, for rapidity |yKK|<0.8 and pT,KK<0.1 GeV/c, the measured coherent photoproduction cross section is dσ/dy=3.37±0.61(stat)±0.15(syst) mb. The center-of-mass energy per nucleon of the photon-nucleus (Pb) system WγPb,n ranges from 33 to 188 GeV, far higher than previous measurements on heavy-nucleus targets. The cross section is larger than expected for φ(1020) photoproduction alone. The mass spectrum is fit to a cocktail consisting of φ(1020) decays, direct K+K- photoproduction, and interference between the two. The confidence regions for the amplitude and relative phase angle for direct K+K- photoproduction are presented

    Neutral to charged kaon yield fluctuations in Pb – Pb collisions at sNN=2.76 TeV

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    We present the first measurement of event-by-event fluctuations in the kaon sector in Pb – Pb collisions at √sNN = 2.76 TeV with the ALICE detector at the LHC. The robust fluctuation correlator νdyn is used to evaluate the magnitude of fluctuations of the relative yields of neutral and charged kaons, as well as the relative yields of charged kaons, as a function of collision centrality and selected kinematic ranges. While the correlator νdyn[K+, K− ] exhibits a scaling approximately in inverse proportion of the charged particle multiplicity, νdyn[K0 S , K± ] features a significant deviation from such scaling. Within uncertainties, the value of νdyn[K0S , K± ] is independent of the selected transverse momentum interval, while it exhibits a pseudorapidity dependence. The results are compared with HIJING, AMPT and EPOS–LHC predictions, and are further discussed in the context of the possible production of disoriented chiral condensates in central Pb – Pb collisions

    Light (anti)nuclei production in Pb-Pb collisions at sNN=5.02 TeV

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    The measurement of the production of deuterons, tritons and 3 He and their antiparticles in Pb-Pb collisions at √s NN = 5.02 TeV is presented in this article. The measurements are carried out at midrapidity (|y| < 0.5) as a function of collision centrality using the ALICE detector. The pT -integrated yields, the coalescence parameters and the ratios to protons and antiprotons are reported and compared with nucleosynthesis models. The comparison of these results in different collision systems at different center-of-mass collision energies reveals a suppression of nucleus production in small systems. In the Statistical Hadronisation Model framework, this can be explained by a small correlation volume where the baryon number is conserved, as already shown in previous fluctuation analyses. However, a different size of the correlation volume is required to describe the proton yields in the same data sets. The coalescence model can describe this suppression by the fact that the wave functions of the nuclei are large and the fireball size starts to become comparable and even much smaller than the actual nucleus at low multiplicities

    Production of pions, kaons, and protons as a function of the relative transverse activity classifier in pp collisions at s \sqrt{s} = 13 TeV

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    Abstract: The production of π±, K±, and ( p )p is measured in pp collisions at √s = 13 TeV in different topological regions of the events. Particle transverse momentum (pT) spectra are measured in the “toward”, “transverse”, and “away” angular regions defined with respect to the direction of the leading particle in the event. While the toward and away regions contain the fragmentation products of the near-side and away-side jets, respectively, the transverse region is dominated by particles from the Underlying Event (UE). The relative transverse activity classifier, RT = NT/〈NT〉, is used to group events according to their UE activity, where NT is the measured charged-particle multiplicity per event in the transverse region and 〈NT〉 is the mean value over all the analysed events. The first measurements of identified particle pT spectra as a function of RT in the three topological regions are reported. It is found that the yield of high transverse momentum particles relative to the RT-integrated measurement decreases with increasing RT in both the toward and the away regions, indicating that the softer UE dominates particle production as RT increases and validating that RT can be used to control the magnitude of the UE. Conversely, the spectral shapes in the transverse region harden significantly with increasing RT. This hardening follows a mass ordering, being more significant for heavier particles. Finally, it is observed that the pT-differential particle ratios (p + p )/(π+ + π−) and (K+ + K−)/(π+ + π−) in the low UE limit (RT → 0) approach expectations from Monte Carlo generators such as PYTHIA 8 with Monash 2013 tune and EPOS LHC, where the jet-fragmentation models have been tuned to reproduce e+e− results

    Inclusive and multiplicity dependent production of electrons from heavy-flavour hadron decays in pp and p-Pb collisions

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    Measurements of the production of electrons from heavy-flavour hadron decays in pp collisions at root s = 13 TeV at midrapidity with the ALICE detector are presented down to a transverse momentum (p(T)) of 0.2 GeV/c and up to p(T) = 35 GeV/c, which is the largest momentum range probed for inclusive electron measurements in ALICE. In p-Pb collisions, the production cross section and the nuclear modification factor of electrons from heavy-flavour hadron decays are measured in the p(T) range 0.5 < p(T) < 26 GeV/c at root s(NN) = 8.16 TeV. The nuclear modification factor is found to be consistent with unity within the statistical and systematic uncertainties. In both collision systems, first measurements of the yields of electrons from heavy-flavour hadron decays in different multiplicity intervals normalised to the multiplicity-integrated yield (self-normalised yield) at midrapidity are reported as a function of the self-normalised charged-particle multiplicity estimated at midrapidity. The self-normalised yields in pp and p-Pb collisions grow faster than linear with the self-normalised multiplicity. A strong p(T) dependence is observed in pp collisions, where the yield of high-p(T) electrons increases faster as a function of multiplicity than the one of low-p(T) electrons. The measurement in p-Pb collisions shows no p(T) dependence within uncertainties. The self-normalised yields in pp and p-Pb collisions are compared with measurements of other heavy-flavour, light-flavour, and strange particles, and with Monte Carlo simulations
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